In the given reaction `HCOONaoverset(400^@C)rarr(X)+(Y)`, (X) and (Y) will be

Options

A. `{:(COONa),(|),(COOH):}and H_2`
B. `{:(COONa),(|),(COONa):}and H_2`
C. `{:(COONa),(|),(COONa):}and H_2O`
D. `{:(COOH),(|),(COOH):}and H_2`

Answer

To solve the problem, we need to analyze the thermal decomposition of sodium formate (HCOONa) when heated to 400°C.

### Step-by-Step Solution:

1. **Identify the Compound**: The compound given in the reaction is sodium formate (HCOONa).

2. **Understand the Reaction**: When sodium formate is heated, it undergoes thermal decomposition. The general reaction for the thermal decomposition of sodium formate can be represented as:
\[ \text{HCOONa} \xrightarrow{heat} \text{Na}_2\text{C}_2\text{O}_4 + \text{H}_2 \]
Here, sodium formate decomposes to form sodium oxalate (Na₂C₂O₄) and hydrogen gas (H₂).

3. **Identify Products (X and Y)**: From the thermal decomposition reaction, we can identify:
- (X) = Sodium Oxalate (Na₂C₂O₄)
- (Y) = Hydrogen gas (H₂)

4. **Conclusion**: Therefore, the products (X) and (Y) from the reaction are:
- (X) = Sodium Oxalate (Na₂C₂O₄)
- (Y) = Hydrogen gas (H₂)

### Final Answer:
(X) = Sodium Oxalate (Na₂C₂O₄)
(Y) = Hydrogen gas (H₂)

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